add getSerialNumber (#46)

- add getSerialNumber, kudos to skunktrading
- add example SHT31_getSerialNumber.ino
- changed defines for commands in static constexpr (.cpp)
- update examples
- update readme.md
- update keywords.txt
- minor edits

* fix build

* fix build

add clearStatus() (#43)

- add **clearStatus()**, kudos to Elbandi
- update readme.md
- removed **heatUp** from documentation, labelled as depreciated.
- add example SHT31_demo_plotter.ino
- update keywords.txt
- minor edits

refactor API, begin + constructor (#40)

- refactor API, constructor and begin()
- add **getAddress()**
- update readme.md
- update examples
- minor edits

fix #38 support Wire1 for ESP32 (#39)

- fix #38 support for Wire1 for ESP32
- update examples
- update readme.md

Prepare for derived SHT31_SW (#37)

- prepare for derived class SHT31_SW
- update readme.md
- update GitHub actions
- update license 2023
- minor edits

add changelog.md (#34)

sync with SHT85 (#30)

update library.json, readme, license, minor edits (#29)

* update library.json, readme, license, minor edits

update build-CI + issue_20 examples (#24)

* update build-CI + new examples for #20

update readme.md (#21)

* update heater code
* update readme.md